In recent years, the use of portable hand-held data terminal units, wireless portable telephones and heads-up display units has become widespread. Portable hand-held data terminal units, for example, are used to track inventory in retail stores and warehouses. Wireless portable telephones have found widespread domestic use as well as commercial use as an alternative to the hard-wired telephone. Heads-up display units have found use in a variety of applications, particularly where it is desirable to free both hands of the user for carrying out other functions.
Portable hand-held data terminal units typically comprise a hand-held housing including a battery, a liquid crystal display (LCD), an alpha-numeric keyboard, a central processing unit (CPU) for processing of data, a memory for storage of data, a speaker and a wireless and/or hard-wire communication device or devices. Wireless communication devices include infra-red or radio transceivers while hard-wire communication devices include serial, parallel and modem interface devices. Typical infrared or radio transceivers can sustain data rates to a host computer from 9600 bps to 10 mbps depending on the sophistication, cost and range required by a user's application. The hand-held data terminal units are often provided with an optional bar code scanning device.
Wireless portable telephones generally comprise a hand-set containing a battery, a numeric keypad for dialing and limited control functions, a processing unit for processing data, a speaker, a microphone and a radio transceiver for communications. The radio transceivers normally support wireless data rates up to 32 kbps which is adequate for the transmission of good quality voice and control signals over a wireless telephone connection. However, this data rate is not sufficient to handle many other high density data transmissions such as that needed to provide a video display. Some wireless portable telephones also have a small LCD display of 10 to 16 characters to provide for display of telephone numbers and call status. The display usually is located on the side of the phone placed against the user's head when talking and listening, and thus the display cannot be viewed during such use of the phone.
Heads-up display units (non-projection type) have comprised a head-mount mechanism from which a small LCD display is suspended approximately 2 to 5 cm in front of one eye of the user. Although the display may have, for example, a 2.5 cm diagonal dimension, a lens is often provided in front of the display to create a virtual image that appears many times larger. The display may provide in essence the equivalent of a typical display associated with a personal computer, such displays commonly consisting of a 25 line by 80 character per line screen. A cable or cables from the head-mount mechanism provide for connection to a computer unit carried on the user's body by suitable means. The computer unit typically contains a battery, display drivers for the LCD display, a CPU for processing data, memory for storage of data and one or more wireless or hard-wire communication devices. In some cases, a microphone and earphone are attached to the head-mount mechanism and are either cabled to the body-mounted computer or communicate therewith via low power radio transceivers.
By way of example, the functions afforded by the aforesaid devices may have use by a doctor that receives an emergency call from a nurse within a hospital. The doctor may be in his/her office, at a meeting, at lunch, etc. Today, the doctor could carry a wireless pager or wireless telephone whereby he/she may be contacted by the nurse. The patient emergency may be discussed over the wireless telephone carried by the doctor or, if the doctor had been contacted by a wireless pager, over a telephone used to call back the nurse. Verbal communications over a telephone, however, may not provide the doctor with all the information he desirably should have to adequately diagnose the patient emergency. For instance, it may be desirable for the doctor to review the patient's medical records maintained in the hospital's records data base while talking to the nurse. An attempt to satisfy this need using known wireless telephones, heads-up display units and wireless data terminal units would require the doctor to carry a data terminal unit, wear a heads-up display unit and also carry a wireless telephone. Such an arrangement would be unacceptable because of ergonomics, cost, weight and other factors.
It would be advantageous if there were a small portable device that the doctor could carry and that would enable voice communications simultaneously with data terminal functions and full screen display of data. This would enable the doctor to converse with the nurse while viewing the patient's medical records on a display just as if he/she was at a computer terminal. Not only would such a device contribute to increased quality of health care with reduced cost and time savings, such a device would have many other desirable, beneficial and advantageous applications as well.